The device of the present disclosure is suitable for pressure vessels for extinguishing agents having an extinguishing liquid that is being expelled by means of a propellant gas from this vessel by a riser to extinguishing lines.
Fire-extinguishing systems of this type are known.
DE 100 48 544 A1 describes a stationary fire-extinguishing system with combined activation and extinguishing line, consisting of an extinguishing-agent vessel having an extinguishing liquid, lines for the extinguishing agent and a propellant-gas vessel having a propellant gas that discharges the extinguishing liquid from the extinguishing-agent vessel into the line for the extinguishing agent. The extinguishing-agent vessel does not feature a compensation tank nor a filling-level display.
99% of the market-standard pressurized-gas cylinders that are used for firefighting techniques exhibit a single threaded socket for example according to DIN EN 629-1-25E.
By providing a suitable interior coating, such cylinders can be converted to water-supply cylinders. Such water-supply cylinders are employed in high-pressure water-fog extinguishing systems.
The small socket of these water-supply cylinders as the only communications opening to the extinguishing medium represents a technical challenge for upgrade solutions that let the water-supply cylinders be upgraded for convenient operation of the fire-extinguishing system.
During operation of the extinguishing system it is expected that the water supply can be checked for wastage and that the thermal influences on the extinguishing liquid caused by the environment such as contraction and expansion can be compensated without any loss.
Pressurized-gas cylinders that are used for gaseous extinguishing agents can be employed as extinguishing-agent vessels. These cylinders are provided with suitable coatings on the inside, and thus water for firefighting can be stored therein protected against corrosion and in the case of a fire is vaporized through suitable nozzles at high pressure for fighting a fire.
Due to variable environmental conditions of these systems, the environmental temperature acts on the stored water such that it changes its volume. The stored water contracts and expands due to changes in temperature. In the case of corresponding environmental conditions (for example in the case of extinguishing lines and open nozzles without valves to the extinguishing-agent vessel) the water can also evaporate.
The prior art is that pressure vessels are filled with liquid extinguishing agents, without compensation tank.
Therefore the necessity for safeguarding the required amounts of extinguishing water or at least of reliably monitoring the required amount of extinguishing water is indispensable.
A problem for monitoring such cylinders consists in the fact that these cylinders only exhibit an extrusion with a threaded socket that just about makes it possible to receive a valve with a riser.
However, changes to such gas cylinders, specifically conversion to water-supply cylinders that potentially can offer further connection possibilities for example for monitoring purposes, would result in high costs for the operating licenses or approvals of the pressurized-gas cylinders.
Another problem consists in the fact that the filling level is monitored inside the extinguishing-agent pressure vessel (inside monitoring in pressure vessels) using only pressure-resistant components (operating pressures of up to several hundred bar). In addition to high costs, also considerable technical effort is involved to transfer the filling-level information out of the pressure vessel.
DE 100 47 594 A1 describes a method and a device for determining the liquid level of a liquid in a vessel. To achieve a reliable display at the critical liquid points, the method dispenses with continually measuring the filling level in the vessel over the entire range, and instead electrodes are disposed in the vessel to determine changes in the filling level and limit values. In this way, filling levels such as “full vessel”, “minimum filling level in the vessel”, and “empty vessel” are defined. To compensate and to document a liquid level in a supply vessel for extinguishing agents, this type of determination of the filling level is unsuitable.
DE 36 13 906 A1 describes a device for content monitoring of expansion tanks subject to a gas pressure and the like, for example heating installations. The device exhibits an expansion tank, the expansion of the liquid in the expansion tank being displayed mechanically or electrically. In this solution, the expansion tank and the corresponding connecting parts exhibit the same pressure resistance, entailing comparable costs.
WO 01/66269 A1 describes a device for determining and/or monitoring a predetermined filling level in a vessel, in which the actual filling level in a vessel is determined by means of oscillations. This device, too, is unsuitable for compensating and measuring the filling level in a supply vessel. Also in this case the monitoring components that are used have to exhibit the pressure resistance of the vessel.
DE 11 2004 000 270 T5 describes the measurement of volumes using pressure, it been possible to pressurize a vessel and sensors for measuring the pressure being arranged inside the vessel. Although the device is suitable to determine a fluid volume in the vessel, it is not suitable to expand it beyond the vessel limit and to determine it. In this case, too, the monitoring components that are used have to feature the pressure resistance of the vessel.
DE-PS 846 303 describes a float-controlled monitoring facility in particular for expansion vessels of heating or cooling installations, where a 3-way cock is arranged below the float vessel, using which the lowering of the liquid level in the expansion vessel can be controlled.